1. Field of the Invention
The present invention relates to a new hinge system useful in eyewear frames, and more particularly, relates to a hinge system having a snap interfit to permit easy interchange or replacement of temples.
2. Description of the Art
Eyewear, such as sunglasses or spectacles, typically comprise a front frame for holding at least one lens, temples which extend out and over the ear of the wearer, and hinges for attaching the temples to the front frame. Conventionally, the front frames comprise a pair of rims each holding a lens and attached by a bridge and/or brace. More recently, the front frames comprise a top member which holds a single unitary lens. Hinges typically consist of two interlocking pieces, one attached to the front frame through either a rim or a top member, and the other attached to the temple, also referred to as an ear stem. The interlocking pieces are connected by a tongue and groove relationship and held together using conventional fasteners such as screws.
With the increased level of sports activity enjoyed today, eyewear, and particularly sunglasses, have been developed to meet the needs of the active wearer. For example, interchangeable eyewear components are now available so that the wearer may change the eyewear to meet their needs based on level of activity and environmental conditions. More specifically, lenses can be interchanged to better compensate for varying light conditions such as early morning, mid day, and late evening sunlight. Temples have also been designed which are interchangeable to meet the wearer's requirements. One such temple can be a conventional paddle temple which is comfortable during leisure, but will not securely hold the eyewear on the wearer's head during active movement. A second such temple can be a cable temple which provides the secure attachment needed when engaged in rapid movement or activities, but which can sometimes be uncomfortable. Finally, interchangeable eyewear components have also been developed for aesthetic purposes allowing the wearer to change colors or styles of the components as desired.
Other hinge systems have been developed for interchangeable temples. For example, U.S. Pat. Nos. 2,210,507, 4,730,915 and 4,824,233 disclose an interchangeable ear stem or temple having a snap interfit wherein the interfit members have a tongue and groove configuration. The frame or temple has outwardly extending flanges spaced vertically from each other with holes which can receive mating projections attached to the other member. However, this system has not proved to be entirely satisfactory since the flanges, holes and projections are highly susceptible to wear and/or breakage and the temples are generally difficult to remove when the projections are large or fit too tightly in the holes.
The present invention provides a novel hinge system with a snap interfit construction which permits easy removal and replacement of the temple yet provides a secure attachment of the temple to the front frame. Further, the invention provides a hinge system which is easy to manufacture. Moreover, this invention provides for a hinge system which is simple to use and which the design makes apparent to the user the manner in which the hinge system functions. Last, the present hinge system can be easily constructed from various metals or plastics.